Apoptosis in asymptomatic HIV-1 seropositives immunized with HIV-1 env glycoprotein (gp160): Effects of administration of Zidovudine in vivo and interleukin-2 in vitro

In this paper we report the effects of VaxSyn® (Protein Sciences Corp.) immunization on spontaneous apoptosis occurring in vitro after culture of PBMC in medium alone in 30 HIV-seropositive patients enrolled in a double- blind clinical trial that included three groups: treatment with VaxSyn, AZT and VaxSyn, and AZT. Our data show no significant modifications in the levels of apoptosis observed in the three groups over the long-term follow-up (up to 720 days). This was not associated with any significant modifications in other clinical or immunological features. However, analysis of apoptosis performed shortly after the first immunization (at days 3 and 7) showed a significant reduction in the rate of apoptosis in patients receiving AZT or AZT and VaxSyn, as compared with patients receiving VaxSyn alone (30.42 ± 2.52 SE at day 0 and 23.74 ± 1.84 at day 3; p = 0.039). Our data also indicate that addition of IL-2 in vitro had a significant inhibitory effect on mortality in all the randomization groups, especially in those receiving AZT (alone or in combination with VaxSyn).